MOSCOW - Mikhail Prokhorov, the owner of the New Jersey Nets basketball team and one of Russia's richest tycoons, said Monday he will run against Prime Minister Vladimir Putin in the March presidential election.

The colorful Prokhorov, who has a net worth estimated at $18 billion according to a report by NBC New York, could pose a serious challenge to Putin, whose authority has been dented by alleged widespread fraud during Russia's Dec. 4 parliamentary election.

Justin Lane / EPA, file

Mikhail Prokhorov, one of the owners of the New Jersey Nets, stands outside of a hotel following an NBA board of governors meeting in New York, on 20 October 2011.

Prokhorov, who is 46 and stands 6 feet 8 inches tall, made his fortune in investments and precious metals, NBC New York reported.

He bought the New Jersey Nets in 2010 for a reported price of $200 million.

Putin's party only won about 50 percent of that vote, compared to 64 percent four years ago, and the fraud allegations have allowed opposition parties to successfully mount massive anti-Putin protests in Russia.

On Sunday, President Dmitry Medvedev promised on his Facebook page that the alleged vote fraud will be investigated. But Putin's spokesman, Dmitry Peskov, predicted Monday the probe will show that little vote fraud occurred and that it had no effect on the outcome of the ballot.

That prediction signaled that Putin — who served as Russia's president in 2000-2008 and only became prime minister because of term limits — is holding firm, despite the protests, which have been the largest here since the 1991 collapse of the Soviet Union.

On Saturday tens of thousands of people in Moscow and smaller numbers in more than 60 other cities protested election fraud and called for an end to Putin's rule.

"The society is waking up," Prokhorov said at his news conference in Moscow.

He will have a good chance of appealing to Russia's growing opposition, which includes prosperous middle-class residents, many of whom are angered by Putin's bid to reclaim the presidency.

Asked whether he is going to join another opposition rally planned later this month in Moscow, Prokhorov wouldn't say, but he added that he agrees with many of the anti-Putin slogans that were shouted out during Saturday's protests.

Prokhorov's presidential bid follows his botched performance in the parliamentary race, when he formed a liberal party under tacit support of the Kremlin, then abandoned the project under what he called Kremlin pressure.

He has personally blamed Vladislav Surkov, a presidential deputy chief of staff, for staging a mutiny within the party's ranks. "I will solve that problem by becoming his boss," Prokhorov said Monday when he was asked whether Surkov could pose obstacles to his presidential bid.